The most in-depth and practical analysis to date of the “3·21” explosion accident in Xiangshui (3)

Safety measures for accident prevention typically encompass intrinsic safety, engineering controls, administrative controls, and personal protective equipment. The implementation of intrinsic safety strategies and the adoption of engineering controls are primarily carried out during the research, development, and design phases. Consequently, to a large extent, the design determines the inherent safety characteristics of a process unit.

Domestic engineering firms (design entities) generally maintain a high level of rigor in adhering to design codes and standards. However, referencing applicable codes and standards is merely the baseline for design; there is still room for improvement. For example:

1. Proactively pursue inherently safe design. Collaborate closely with the company’s R&D and process engineering departments to enhance the safety of process units by adopting an inherently safe design approach—covering aspects such as plant layout, storage limits for hazardous materials, material handling, design specifications for critical equipment (including material selection), choice of heating media, and fault‑tolerant operating procedures—while prioritizing solutions that maximize safety wherever possible.

    

2. Collaborate with safety consulting firms or risk assessment organizations to refine the design scheme based on the findings of the risk assessment. For example, when developing the layout of process units, in addition to adhering to relevant standards and codes, you can also leverage the quantitative simulation results provided by the consulting firm regarding the consequences of severe accidents to optimize the layout—particularly by prioritizing measures to mitigate risks in high‑occupancy areas such as the central control room and administrative office buildings.

3. Process hazard analysis is a critically important step in enhancing design safety, yet many still fail to fully appreciate its significance. During the design phase, the engineering team should place greater emphasis on chemical process hazard analysis—including hazard and operability studies, or HAZOP analyses—actively participate in and support HAZOP activities, and allocate sufficient time in the project schedule to carry out this work.

   Note: At present, there are relatively few organizations in the market that offer high‑quality process hazard analysis services, such as HAZOP studies and SIL rating. Some engineering firms have also entered this field ahead of others. If an engineering firm undertakes such work, it must establish appropriate mechanisms to address internal conflicts of interest; otherwise, if the person leading the process hazard analysis and the designers are colleagues—often even from the same department—they may “go easy” on certain potential accident scenarios, thereby creating hidden safety risks. In foreign‑invested enterprises operating in China, it is typically the company itself (or a third party commissioned by the company) that leads the process hazard analysis, with the engineering firm participating and providing support.

4. Enhance the capability to apply critical safety technologies. At present, many small and medium-sized engineering firms (design institutes) in China still exhibit relatively weak competencies in the application of certain key safety technologies. For example, in the past, due to a lack of reaction‑heat data, many safety relief devices were sized based on experience or by suppliers, without detailed release‑quantity calculations. Since 2017, following national requirements to conduct reaction‑heat measurements and risk analyses for fine chemical processes, numerous hazardous reactions now have available reaction‑heat data, enabling engineering firms to leverage this information for designing relief systems, including calculating emergency relief capacities. Consequently, it is necessary to develop corresponding computational capabilities—particularly for two‑phase flow relief scenarios. Moreover, in areas such as safety instrumented systems, explosion‑proof zoning (which should go beyond merely referencing GB 50058 as a guideline), and dust‑explosion prevention, many of our design organizations need to strengthen their technical expertise.

5. Among third-party stakeholders, equipment manufacturers play a crucial role—though we will set them aside for now. Chemical‑process equipment has a profound impact on safety across the chemical industry. Unfortunately, many manufacturers still hold outdated safety philosophies, focusing primarily on achieving process objectives while paying insufficient attention to safety considerations. For example, rotating machinery often features guard covers that protect only half of the moving parts, and numerous dryers and dust collectors used for combustible powders fail to incorporate essential explosion‑safety measures, such as pressure‑relief panels. A decade ago, obsolete centrifuges were ubiquitous, leading to frequent accidents; in recent years, manufacturers have adopted nitrogen‑inerting systems and enclosed, automated operations—some of which have been retrofitted by the plants themselves—resulting in a marked reduction in incidents. Design firms serve as the bridge between end‑users and equipment manufacturers. If these firms articulate safety requirements more comprehensively and clearly when drafting equipment technical specifications, they can not only help mitigate safety risks in ongoing projects but also encourage manufacturers to learn and improve. As a result, equipment safety is enhanced, and the entire industry’s safety awareness and overall performance are elevated.

6. Promote the refinement of regulations and technical standards. Some design firms have chaired or participated in the development of national safety‑related codes and technical standards, with their contributions widely recognized. Design firms can also establish more effective feedback mechanisms, encouraging engineers to report issues encountered in applying these codes and standards, consolidating such concerns, and providing timely responses—actions that greatly facilitate the improvement of relevant safety regulations and standards. Of course, government regulatory agencies and standard‑setting bodies should likewise put in place convenient channels for receiving and addressing feedback.

The deliverables of engineering firms (design entities) constitute a critical material foundation for ensuring the safety of process units. While we have many high‑caliber engineering companies, there remains considerable room for improvement in safety‑oriented design concepts and methodologies.

At present, all safety‑assessment entities are undergoing transformation, and the success of this transition will have a profound impact on overall safety in the chemical industry. If the transformation is successful, a large number of specialized safety‑consulting firms will emerge, which would be a boon for chemical enterprises.

The safety assessment organizations bring together many highly qualified experts. In the past, when they were busy producing standardized safety assessment reports, many of these experts were unable to fully leverage their professional strengths. The current move to promote socialized services represents an excellent effort to unlock their full potential.

In the United States and Europe, there are numerous safety consulting firms of varying sizes; some may be small, yet highly specialized in specific domains. To ensure safety in the chemical industry, we too need a robust cadre of expert consultants to support enterprises. At present, professional consulting firms in China remain relatively few, and safety‑assessment agencies hold promise as key players in filling this gap—though their transition will by no means be easy.

How can safety assessment firms successfully transform? Many such firms are still exploring the issue and even grappling with it. Here are a few suggestions for your reference:

1. The safety management and technical expertise of corporate managers and engineers are steadily improving, leading to a declining demand for generic, one-size-fits-all assistance. What enterprises now require are in-depth, specialized services. We should focus on developing professional risk‑control solutions tailored to businesses; in this regard, many safety‑assessment firms still need to elevate their technical capabilities by adopting cutting‑edge international safety technologies and best‑practice management approaches. Chemical‑industry safety is an exceedingly broad field, and some organizations have sought to take on everything, pursuing whatever is most profitable—yet this approach may no longer be viable going forward. As they undergo transformation, safety‑assessment firms can choose to specialize in a particular area, cultivating deep expertise in that niche. This not only enables companies to derive greater value but also paves the way for the assessment firms themselves to achieve sustainable business growth.

2. Providing concrete, actionable solutions. Many small and medium-sized chemical enterprises have relatively weak in-house safety expertise and limited engineering experience and capabilities; simply identifying problems is of little practical value to them. The key lies in helping them address real‑world challenges, particularly by delivering tailored, context‑specific solutions. The industry urgently needs a robust cohort of safety consulting firms that can deliver such pragmatic, turnkey solutions. If safety assessment agencies can rise to this standard, the transformation will be largely successful.

3. Government requirements for corporate compliance—ensuring adherence to legal and regulatory standards—are becoming increasingly stringent. Higher levels of compliance naturally reduce operational safety risks. Providing assistance and guidance to chemical enterprises in meeting applicable laws, regulations, and standards is highly valuable—and precisely where environmental assessment firms excel. Consider offering companies more comprehensive and specialized compliance support and services.

A major challenge hindering the transformation of safety‑assessment firms is the long‑standing “ultra‑low‑price strategy” that has characterized their operations. Many such agencies have become accustomed to competing on price, and this pricing approach has been one of the key factors contributing to the previously subpar quality of safety‑assessment services.

In the fields of safety management and safety‑related technical services, seemingly low prices often come at the expense of quality; for enterprises, what appears to be a cheap service may in fact prove to be the most costly. Winning contracts through rock‑bottom pricing inevitably leads to compromises in service—forcing firms to hire underqualified personnel with limited experience—and while this may shave off some costs, it can result in far greater losses during the engagement. A single misguided recommendation can significantly inflate unnecessary expenditures, sow hidden risks, and even trigger major accidents. To ensure the healthy development of the entire industry, we must abandon the destructive practice of cutthroat price competition. Prolonged low‑price rivalry drives out high‑quality providers, causing top talent to leave the field and leaving chemical companies struggling to secure the professional services they truly need. We should oppose excessive profiteering, but reasonable profits are essential for sustaining the industry’s long‑term growth. We look forward to a wave of safety‑assessment firms reinventing themselves, transforming into trusted partners that help chemical enterprises mitigate operational risks.

Since the very first chemical plant was established, chemical safety has been a concern. However, many of us who study chemical engineering still lack sufficient knowledge of safety, a shortcoming that is largely attributable to gaps in our university education.

In some foreign universities, chemical process safety has already become a dedicated academic discipline, whereas in China, only a few institutions offer it as a mandatory course. It is essential to make chemical process safety a compulsory subject for students majoring in chemical engineering, or at the very least to integrate its key concepts into existing undergraduate and associate‑degree curricula, thereby helping students develop fundamental, accurate understanding and sound principles.

A well-known British university (with a campus in China) annually invites industry experts to help review its chemical engineering curriculum, strategically integrating key process‑safety concepts and cutting‑edge practices into students’ learning pathways—from the first year through graduation. This approach enables students to understand how the industry approaches chemical safety at both the conceptual level and in terms of the core knowledge and methodologies required to ensure the safe operation of chemical plants, as well as the tools, software, and technical standards currently employed in the field. Over the past few years, I have been invited to participate in these review meetings and have also taken time to deliver specialized lectures on process safety to the university’s chemical engineering graduates. I am keenly hopeful that many domestic universities will adopt this model to cultivate their students.* [Note] Today’s students will become tomorrow’s engineers, managers, government officials, or business owners in our chemical industries; the foundational safety awareness they develop during their academic years will have a profoundly lasting impact.

Note: The author has consulted with Professor Zhao Jinsong, Head of the Department of Chemical Engineering at Tsinghua University. At present, the Department of Chemical Engineering at Tsinghua University employs a curriculum review process similar to the one described above, and some other universities may be adopting comparable practices as well.

Now, even domestic universities with chemical engineering programs are beginning to place greater emphasis on education related to chemical safety. However, many university instructors possess strong theoretical expertise but lack hands-on experience in actual production settings, making it difficult to bridge the gap between theory and practice. How to effectively integrate industry best practices with university teaching is a question worth exploring. Recently, some universities have invited industry experts and academic faculty to co-author textbooks on safety, health, and the environment (EHS)—a highly commendable initiative!

Moreover, in recent years, safety engineering has become an extremely popular field of study. Given the unique nature of chemical‑process safety, if a safety engineering program is designed to serve the chemical industry, it must not only equip students with sound safety principles, knowledge, and skills, but also ensure they acquire relevant process and engineering expertise—covering courses such as chemical engineering principles and physical chemistry.

I primarily work with enterprises, and my views on the aforementioned third-party organizations are based on distant observation, inevitably tinged with partiality and a tendency to see only part of the picture. However, one thing is beyond doubt: these third-party agencies are vital partners for chemical companies in achieving safety; when they perform well, they can help the chemical industry reduce catastrophic accidents. (To be continued)